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81.
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Adenoid cystic carcinoma (ACC) of the head and neck region is an uncommon epithelial tumor of the major and minor salivary glands. In the oral region, although ACC arising from the minor salivary glands is the second most commonly found tumor in the tongue base, its occurrence in the anterior part of the tongue is rare. Histopathologically, ACC is categorized into three growth patterns (tubular, cribriform, and solid types) and three histologic grades (I?CIII) that are based on the proportions of these patterns. According to this classification, tubular- and cribriform-type ACCs are considered to be lower grade lesions, while solid-type ACCs are considered to be higher grade lesions. A fourth histopathological type has recently been reported by some authors, namely, dedifferentiation or high-grade transformation of ACC. However, very few studies have focused on the imaging features of these ACCs. We report here the case of a 63-year-old female patient with ACC of the tongue with dedifferentiated components, together with the radiological images and pathological features of this ACC.  相似文献   
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ObjectivesTo retrospectively assess the significance of gender as a predictor of intravesical recurrence following nephroureterectomy for urothelial carcinoma of the upper urinary tract (UC-UUT).Materials and methodsThis study included 502 consecutive patients (360 male and 142 female) who were diagnosed as having clinically localized UC-UUT and underwent nephroureterectomy. Clinicopathologic outcomes of these patients were analyzed focusing on the impact of gender.ResultsThe incidence of intravesical recurrence in male patients (41.9%) was significantly greater than that in female patients (27.5%). Despite the lack of significant differences in cancer-specific and overall survivals with respect to gender, the intravesical recurrence-free survival in male patients was significantly worse than that in female patients. Of several parameters examined, univariate analysis identified gender, tumor site, and tumor focality as significant predictors of intravesical recurrence following nephroureterectomy. Of these, only gender and tumor site appeared to be independently associated with intravesical recurrence-free survival on multivariate analysis. Furthermore, there was a significant difference in intravesical recurrence-free survival according to positive numbers of these two independent factors; that is, intravesical recurrence occurred in 12 of 55 patients who were negative for both risk factors (21.8%), 96 of 280 positive for a single risk factor (34.3%), and 82 of 167 positive for both risk factors (49.1%).ConclusionsThe incidence of intravesical recurrence following nephroureterectomy for UC-UUT is comparatively high. Therefore, it would be potentially important to perform careful follow-up targeting intravesical recurrence for such patients, particularly for male patients and/or patients with tumor located at the ureter.  相似文献   
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Three very elderly (over 80 years old) patients having generalized myasthenia gravis without thymoma were treated with cyclosporin A and followed for up to 24 months. Cyclosporin A therapy quickly improved myasthenia gravis symptoms in all cases, which allowed a rapid reduction in the prednisolone dose and improvement of prednisolone-related hyperglycemia and hypertension. Combination therapy with prednisolone and low-dose cyclosporin A not only improved the clinical symptoms of the very elderly myasthenia gravis patients but also resulted in a rapid reduction in prednisolone dosage and prednisolone-related side effects. Attention should be paid to cyclosporin A-related renal dysfunction.  相似文献   
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Resection of the superior or lateral wall of the cancer-affected oropharynx can often lead to disturbed nasal breathing, dysphagia, and dysarthria. The authors used the Gehanno method to reconstruct these surgical defects and achieved favourable functional recovery soon after surgery. The present study was undertaken to analyze the long-term outcome and usefulness of this method. Reconstruction was carried out using the Gehanno method in 36 patients during the 10-year period between 1997 and 2007. Both short-term and long-term evaluations of the postoperative function were performed in 12 of the 36 cases. The postoperative function was favourably maintained in all 12 cases, but gradual deterioration was noted in some cases in which the forearm flap had been used for reconstruction. Conventionally, the forearm flap is considered suitable for the reconstruction of complex structures such as the oropharynx because of its excellent flexibility. The results suggest that if the forearm flap is used for reconstruction using the Gehanno method, the surrounding tissue is likely to undergo change over time. The rectus abdominis myocutaneous flap should be considered as the first-choice flap for reconstruction using the Gehanno method.  相似文献   
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Hyponatremia is the most common clinical electrolyte disorder. Once thought to be asymptomatic in response to adaptation by the brain, recent evidence suggests that chronic hyponatremia may be linked to attention deficits, gait disturbances, risk of falls, and cognitive impairments. Such neurologic defects are associated with a reduction in quality of life and may be a significant cause of mortality. However, because underlying diseases such as adrenal insufficiency, heart failure, liver cirrhosis, and cancer may also affect brain function, the contribution of hyponatremia alone to neurologic manifestations and the underlying mechanisms remain unclear. Using a syndrome of inappropriate secretion of antidiuretic hormone rat model, we show here that sustained reduction of serum sodium ion concentration induced gait disturbances; facilitated the extinction of a contextual fear memory; caused cognitive impairment in a novel object recognition test; and impaired long-term potentiation at hippocampal CA3–CA1 synapses. In vivo microdialysis revealed an elevated extracellular glutamate concentration in the hippocampus of chronically hyponatremic rats. A sustained low extracellular sodium ion concentration also decreased glutamate uptake by primary astrocyte cultures, suggesting an underlying mechanism of impaired long-term potentiation. Furthermore, gait and memory performances of corrected hyponatremic rats were equivalent to those of control rats. Thus, these results suggest chronic hyponatremia in humans may cause gait disturbance and cognitive impairment, but these abnormalities are reversible and careful correction of this condition may improve quality of life and reduce mortality.  相似文献   
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